不同倾角充-岩组合体三轴压缩力学特性及破坏特征  

The triaxial compressive mechanical properties and failure characteristics of backfill-rock combined bodies with different interface angles

作　　者：徐文彬[1] 陈伟[1] Xu Wenbin;Chen Wei(School of Energy and Mining Engineering,China University of Mining and Technology-Beijing,Beijing 100083,China)

机构地区：[1]中国矿业大学(北京)能源与矿业学院,北京100083

出　　处：《矿业科学学报》2023年第5期633-641,共9页Journal of Mining Science and Technology

基　　金：国家重点研发计划(2018YFE0123000);中央高校基本科研业务费专项资金(2023JCCXNY01)。

摘　　要：为探究交界面倾角β对充填体与围岩组合体(充-岩组合体)三轴力学特性影响规律,开展β为0°、15°、30°、45°和60°的充-岩组合体三轴压缩试验,对比分析了不同交界面倾角组合体的力学特性、破坏特征与强度演化规律。试验结果表明:当β≤30°时,组合体的应力-应变曲线可划分为孔隙压密、弹性变形、塑性变形和破坏发展4个阶段,其破坏特征以充填体压剪破坏为主;随着交界面倾角增加,组合体在达到峰值强度后应力陡降,无明显塑性变形和破坏发展阶段,其破坏特征由充填体内部压剪破坏逐渐转变为沿交界面滑移破坏;组合体的峰值强度随着交界面倾角增加先增大后减小,β=30°时峰值强度达到极大值。基于单弱面理论得到组合体滑移破坏的交界面临界倾角为57°~68°,其中β=60°时组合体发生沿交界面滑移破坏,理论计算与试验结果相吻合。This study proposes to explore the effect of interface anglesβon the triaxial mechanical properties of backfill and surrounding rock combined bodies(backfill-rock combined bodies)by conducting a triaxial compression experiment of backfill-rock combined bodies with interface anglesβof 0°,15°,30°,45°and 60°.This paper compared and analyzed the mechanical properties,failure characteristics and strength evolution patterns of the combined bodies with different interface angles.The experimental results show that:Whenβ≤30°,the stress-strain curve of the combined bodies can be divided into four stages:pore compaction,elastic deformation,plastic deformation and failure development.Its failure characteristics are mainly compression shear failure of the backfill.With the increase of the interface angles,the combined bodies stress drops steeply after reaching the peak strength,without significant plastic deformation or failure development stage.Its failure characteristics gradually change from compression shear failure inside the backfill to sliding failure along the interface.The peak strength of the combined bodies first increases and then decreases with the increase of the interface angles,and peak strength reaches a maximum value whenβ=30°.Based on the theory of single weak plane,the interface critical angles for sliding failure of the combined bodies is 57°to 68°.Whereβ=60°,the combined bodies occurred sliding failure surface along the interface,and the results from theoretical calculation confirm the experimental results.

关 键 词：充-岩组合体 交界面倾角 力学特性 破坏特征 

分 类 号：TD315[矿业工程—矿井建设]